This invention relates to collagen coated cell growth plates, and particularly to a storage stable, collagenous cell growth coating, deposited on cell growth plates, for culturing cells in vitro.
"Natural insoluble collagen" as used herein means and refers to collagen which cannot be dissolved in an aqueous alkaline or in any inorganic salt solution without chemical modification and includes hides, splits, and other mammalian or reptilian coverings. The primary source of natural insoluble collagen is the corium, which is the intermediate layer of a bovine hide between the grain and the flesh sides.
A process for preparing macromolecular biologically active collagen from natural insoluble collagen is disclosed in U.S. Pat. No. 4,279,812. That patent discloses a process for dissolving and regenerating collagen fiber, which removes substantially all impurities from the collagen source and provides a substantially pure collagen product which is biologically active and substantially non-antigenic.
In general, it has been known for many years that the growth of cells in tissue culture is extensive on collagen gels. Collagenous substrata are effective in promoting cell growth in culture conditions for a variety of cells and cell differentiation. See, Biochemistry of Collagen, p. 457, Edited by G. N. Ramachandran and A. H. Reddi, 1976 Plenum Press.
The use of collagen as a cell growth medium has also been disclosed in U.S. Pat. No. 4,352,887 to enable successful culture substrates and culture solutions for in vitro culturing of differentiated cells. As needed, the collagen solutions are disposed in the usual laboratory dishes, such as the Petri dish, and thereafter the cell material is added and permitted to grow. In all instances the collagen is prepared and disposed in the dishes by a separate procedure before use.
A need, therefore, remains for stable, universal, cell growth plates which can be precoated with collagen and which can maintain reasonable shelf life when kept at room temperature without any significant decrease in cell growth support properties.